Traditional methods of yarn production involve a number of segmented batch processes including reeling, dyeing, extraction, drying and winding of the yarn. Batchwise processing in general is extremely labor intensive, accounting for a disproportionate share of production costs as labor costs tend to be relatively high in comparison to other production costs. Batch dyeing of yarn in particular is a disproportionately costly process because compounding the problem of high labor costs are other inherent high cost disadvantages unique to the batch dyeing process.
In the batch dyeing process, a dye bath solution is prepared and a skein of yarn is immersed in the solution until the yarn becomes impregnated with the dyestuff. The skein is then removed from the solution and the spent solution is disposed. This process consumes a tremendous amount of energy and water, the cost of which, like labor, is relatively high in comparison to other production costs. For example, more than 85% of the total energy used in the production of yarn is consumed during the dyeing process.
As such a dyeing process is needed which cost effectively reduces energy and water consumption as well as labor intensity. This need is driven not only by the desire to cut costs, but by the increasing restrictiveness of environmental regulations as applied to manufacturing industries. The reduction of water and energy consumption reduces the environmental impact of the process by reducing the volume of waste effluent produced thereby. Accordingly, it is particularly desirable to develop a more environmentally compatible yarn dyeing process which has significantly lower energy, water and labor requirements than dyeing processes presently known in the art.